we were unable to open to open this addressbook

After a host of problems with Ubuntu 8.04 I reinstalled 7.10. Now when I try to open the addressbook in Evolution I get an error message "Error loading addressbook. We were unable to open this addressbook. Please check that the path /home/us/addressbook/local/system exists, and that you have permission to access it.

The path is correct, and I do have permission, and the .db files are still at the location. This has previously been reported as questions 19863 and 27074, with apparently no solution.

Can anybody help, please? An email app with no addressbook is not a great deal of good to me, but if I install 8.04 I will have even more things broken. (I wish I had just stayed with 7.10 while evrything was working!)